Report - PEER - University of California, Berkeley

nonlinear dynamic) and when they should not be used. Emphasis in researchshould be on the development of nonlinear analysis procedures. For nonlinearstatic (pushover) analysis, additional research is needed on extension to irregularstructures (particularly unsymmetrical) and structures with significant highermode effects. Nonlinear dynamic procedures need improvement of largedisplacement predictions and of element hysteretic models.(6) More work needs to be done in defining appropriate performance measures, withan emphasis on providing protection against life-safety hazards and excessiveeconomic losses.Working Group on Performance-Based Design ConceptsCo-Chairs: Deierlein and FardisRecorder: AschheimWorking Group Members: Aydinoĝlu, Bachman, Bommer, Bonelli, Booth,Chopra, Comartin, Cornell, Fajfar, Fischinger, Ghobarah, Hamburger,Hutchinson, Kabeyasawa, Kawashima, Kowalsky, Krawinkler, Manfredi,Miranda, Otani, Pinho, Pinto P., Porter, Rutenberg, Shiohara, Sucuoĝlu, Tso,Whittaker, Dolšek, Franchin, Iervolino, Poljanšek, Sigmund, ZevnikConclusions and Recommendations(1) The goal of performance based seismic design (PBSD) is to assist in theengineering of cost-effective facilities, whose safety and resistance to damagefrom earthquakes meet the needs and expectations of key stakeholders andsociety at large more effectively and reliably than can be achieved with codesusing prescriptive design rules. Key incentives for the use of PBSD include:(a) Reduction in the initial capital costs of facilities designed to havecomparable performance to that implied by existing standards based onprescriptive rules.(b) Ability to design higher-performance structures that have improved safetyand lower life-cycle costs associated with seismic risk.(2) The most immediate need for and benefit from PBSD are for existing structuresand new facilities with special features that are not adequately addressed byexisting codes (e.g., innovative new structural systems, bridges on liquefiablesoils, and industrial plants with complex geometries).(3) Efforts should be continued to demonstrate the benefits that PBSD will provideto key stakeholders and, thereby, to the engineering professionals who embracePBSD in design practice. This should include pilot applications to both specialfacilities that cannot be reliably designed using current codes and standards, andto more conventional facilities.xv